Asymmetric Syntheses by Optically Active Aminothiol Compounds. IV

A simple asymmetric organocatalytic approach to optically active cyclohexenones.

Optically active 2,5-disubstituted-cyclohexen-2-one derivatives have been prepared in a one-pot process consisting of five reaction steps: an organocatalytic asymmetric conjugated addition of beta-ketoesters to alpha,beta-unsaturated aldehydes that proceeds in aqueous solutions or under solvent-free conditions has been implemented in a multi-step process.

Ultrahigh responsivity of optically active, semicondUcting asymmetric nanochannel diodes

LLE Review, Volume 143 167 Introduction Room-temperature nanodevices based on quantum confinement and/or ballistic nonlinearities are intrinsic nanostructures, not simply scaled-down conventional circuitry, and are gaining wide-spread research attention. Among the nanodevices, one of the most popular is the asymmetric nanochannel diode (ANCD), also referred to as a self-switching diode (SSD), f...

Optically Active Coordination Compounds. Part 50.' 4-Fold Symmetry Axes in Optically Active Complex Ions from Natural Nicotine

Optically active calixarenes conduced by methylene substitution.

The first method for the synthesis of optically active calix[4]arenes that are chiral as a result of substitution on the methylene bridges is described. The key step in the synthesis involves the reaction of a biscarbene complex with a diyne, which generates two of the benzene rings and the macrocyclic ring of the calix in a single transformation. The utility of this triple annulation process i...

Are lignins optically active?

The accepted derivation of lignins from non(enzymatically)-controlled radical coupling reactions has been recently challenged, and it is relevant to ascertain unequivocally whether lignins are or are not (as normally assumed) optically active. Two approaches were used. First, DFRC (derivatization followed by reductive cleavage) dimers derived from beta-5- and beta-beta-units in pine lignins, wh...